I would like to have my program initiate another program during the course of its execution. my code writes some files to disk, and I'd like to spawn off another program to merge those files. My main program keeps running while the merging occurs in the background. I was recommended fork and exec as a tool for this job, but I've never used these before, and can't really say that I understand how they work. here is what my routine is: 
sub logMergeManager
{
        my $writeCounter = $_[0];
        #a trick for implementing logarithmic merging

        $level = 1;
        for(my $ct = 2; $ct <= $writeCounter; $ct*=2)
        {
                if($writeCounter%$ct == ($ct -1) && $writeCounter > 0)
                {
                        push(@forkArray, $level);
                        push(@forkArray, $writeCounter);
                        my $nextMerge = ($ct/2);
                        push(@forkArray, $nextMerge);

                }
                else
                {
                        last;
                }

                $level++;
        }
        if(fork())
        {
                for(my $ct = 0; $ct <= $#forkArray; $ct+=3)
                {
                        my $level = $forkArray[$ct];
                        my $mergeLast = $forkArray[$ct+1];
                        my $mergeFirst = $forkArray[$ct+2];
                        my $dir = '/data/c6/indexes/';
                        my $name2 = $dir.$level."_indexBlock_".$mergeL
+ast;
                        my $name1 = $dir.$level."_indexBlock_".$mergeF
+irst;
                        exec "./indexes/merge2.pl $name1 $name2";
                }
        }

}

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almost certainly this is a terrible example of perl code, but i'm trying! when i run my code since i've implemented this, almost right away everything shuts down, all memory is used and the computer freezes, only to be saved by ^C. can anyone tell me what i'm doing wrong? forgive my noob-ness.

In reply to meddling with forces I can't understand by downer

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